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This document is an editorial discussing the topic of "Environmental and Health Issues and Solutions for Anticoccidials and Other Emerging Pollutants of Special Concern." The editors proposed this topic due to the ongoing importance of emerging pollutants. The editorial highlights the papers that were accepted for publication in this topic, with six papers published in the journal Processes and three in Sustainability. The document also emphasizes the need for specific research on anticoccidials as environmental pollutants. The editors view this topic as a complement to a previous topical issue on emerging pollutants and emphasize the importance of quantifying and addressing these challenges. [Extracted from the article]

The economic yield of saffron (Crocus sativus L.) has a wide range in different parts of the world, and it is not clear why this considerable difference exists. In this research saffron yield and yield components of 13 fields with varied geographic and climatic conditions were studied to determine which factor(s) are more important. Among the studied factors, temperature, field age, soil texture, bulk density, soil and water pH, irrigation events, and growth period had the greatest effect on saffron yield. The highest dry stigma weight, as economic yield, was obtained in three regions of Birjand (27 kg ha−1), Sarayan (24 kg ha−1), and Golshan (23.5 kg ha−1), followed by Neyshabur (18 kg ha−1) and Kashmar (17.5 kg ha−1), which had lower temperatures, coarse soil, balanced soil, and water pH, and longer growth periods. The average yields were increased until the sixth or seventh year (20.8 kg ha−1) and then decreased, however, it seems to be economic before the 10th year. Lower temperatures in early fall were important to stimulate flowering and increase yield in that year, and warm and sunny days in the spring are important for next year yields. We found that the optimal temperature for the first irrigation is ∼16°C and for flowering is ∼5°C–10°C. High‐yield fields did not have higher irrigation water volumes but more irrigation events (6.3), resulting in less water volume per irrigation. No direct relationship was observed between manure consumption and yield; however, processed manure increases yield by improving the soil structure and moisture retention ability. Fields with a complete chemical fertilizer composition had higher yields. It was concluded higher yields are achieved in saffron fields where regions are higher in altitude (at least 1300 m) and lower temperature in early autumn with complete fertilizer composition (especially sulfur and iron). There was no evidence of high salinity sensitivity of saffron. Core Ideas: High temperatures are the main factor limiting development of saffron in new regions.Soil texture, bulk density, and soil and water pH influence the saffron yield.Saffron yield is affected by the irrigation frequency rather than irrigation volume.The saffron field yield increases until the sixth to seventh years and then decreases.A practical pattern was drowned for optimum air temperature during growing cycle. [ABSTRACT FROM AUTHOR]

Among various forms of anthropogenic pollution, the release of toxic metals in the environment is a global concern due to the high toxicity of these metals towards living organisms. In the last 20 years, sediment washing has gained increasing attention thanks to its capability to remove toxic metals from contaminated matrices. In this paper, we propose a Response Surface Methodology method for the washing of selected marine sediments of the Bagnoli-Coroglio Bay (Campania region, Italy) polluted with arsenic and other contaminants. We focused our attention on different factors affecting the clean-up performance (i.e., liquid/solid ratio, chelating concentration, and reaction time). The highest As removal efficiency (i.e., >30 μg/g) was obtained at a liquid/solid ratio of 10:1 (v/w), a citric acid concentration of 1000 mM, and a washing time of 94.22 h. Based on these optimum results, ecotoxicological tests were performed and evaluated in two marine model species (i.e., Phaeodactylum tricornutum and Aliivibrio fischeri), which were exposed to the washing solutions. Reduced inhibition of the model species was observed after nutrient addition. Overall, this study provides an effective tool to quickly assess the optimum operating conditions to be set during the washing procedures of a broad range of marine sediments with similar physicochemical properties (i.e., grain size and type of pollution). [ABSTRACT FROM AUTHOR]

Several studies have shown that combining TiO2 and Cu2O enhances the photocatalytic activity of the material by generating a heterojunction capable of extending the light absorption in the visible and reducing the electron-hole recombination rate. Ball milling has been chosen as an alternative methodology for photocatalyst preparation, among the several techniques documented in the literature review. The results of a previously reported investigation enabled the identification of the most effective photocatalyst that can be prepared for hydrogen generation by combining Cu2O and TiO2 (i.e., 1%wt. Cu2O in TiO2 photocatalyst prepared by ball-milling method at 200 rpm and 1 min milling time). To optimize photocatalytic hydrogen generation in the presence of the greatest photocatalyst, the effects of (i) sacrificial species and their concentration, (ii) temperature, and (iii) pH of the system are taken into account, resulting in a light-to-chemical energy efficiency of 8% under the best-tested conditions. Last but not least, the possibility of using the present photocatalytic system under direct solar light irradiation is evaluated: the results indicate that nearly 60% of the hydrogen production recorded under sunlight can be attributed to the visible component of the solar spectrum, while the remaining 40% can be attributed to the UV component. [ABSTRACT FROM AUTHOR]

Anaerobic ammonium oxidation (anammox) has shown success in past years for the treatment of municipal and industrial wastewater containing inorganic nutrients (i.e., nitrogen). However, the increase in polycyclic aromatic hydrocarbon (PAH)-contaminated matrices calls for new strategies for efficient and environmentally sustainable remediation. Therefore, the present review examined the literature on the connection between the anammox process and PAHs using VOSviewer to shed light on the mechanisms involved during PAH biodegradation and the key factors affecting anammox bacteria. The scientific literature thoroughly discussed here shows that PAHs can be involved in nitrogen removal by acting as electron donors, and their presence does not adversely affect the anammox bacteria. Anammox activity can be improved by regulating the operating parameters (e.g., organic load, dissolved oxygen, carbon-to-nitrogen ratio) and external supplementation (i.e., calcium nitrate) that promote changes in the microbial community (e.g., Candidatus Jettenia), favoring PAH degradation. The onset of a synergistic dissimilatory nitrate reduction to ammonium and partial denitrification can be beneficial for PAH and nitrogen removal. [ABSTRACT FROM AUTHOR]

This study proposes the phytoremediation of phenanthrene (PHE)-, pyrene (PYR)-, and copper (Cu)-contaminated soil by Cannabis sativa L. The experimental campaign was conducted in 300 mL volume pots over a 50 d period using different initial polycyclic aromatic hydrocarbon (PAH) concentrations, i.e., 100 (PC1), 200 (PC2), and 300 (PC3) mg ƩPAHs kg−1 dry weight of soil, while maintaining a constant Cu concentration of 350 mg∙kg−1. PHE and PYR removal was 93 and 61%, 98 and 48%, and 97 and 36% in PC1, PC2, and PC3, respectively, in the greenhouse condition. The highest Cu extraction amounted to 58 mg∙kg−1. In general, the growth of C. sativa L. under the PC1, PC2, and PC3 conditions decreased by approximately 25, 65, and 71% (dry biomass), respectively, compared to the uncontaminated control. The present study is aimed at highlighting the phytoremediation potential of C. sativa L. and providing the preliminary results necessary for future field-scale investigations. [ABSTRACT FROM AUTHOR]

This work investigates a statistical approach analysing data from monitoring activities on marine-coastal areas for environmental quality determination and surveillance. Analyses were performed on a database of the Environmental Protection and Prevention Agency of the Puglia Region. As, Cr, Ni, and Pb concentration values in marine sediments and biota from 2013 to 2015 and 2017 were processed to investigate different contaminant characteristics. Hierarchical cluster analysis identified three contaminant distribution classes with (1) highest Cr, Ni, and Pb concentrations, (2) highest As concentration, and (3) lowest contaminants concentration. The Kruskal-Wallis and Friedman tests showed that contaminant distributions were statistically different when considering the monitoring years and classes. However, statistical similarities resulted during the 2013–2017 and 2014–2015 periods. Spearman's coefficients displayed positive correlations among the pollutants in each matrix and mainly negative correlations for matrices comparison. This methodology aims to provide a practical support for monitoring to identify potential environmental deterioration over time and correlations with specific contamination sources. [ABSTRACT FROM AUTHOR]

The role of nitrogen (N) in inducing salt stress tolerance in plants is not well understood, and the question is more complicated in saffron (Crocus sativus L.), which is sensitive to both nitrogen rates and salinity. The present study was conducted to investigate the effects of different N (0, 50 and 150 kg ha−1) supplies on saffron growth and ions concentration in shoots under several salt stress levels (0, 3, 6 and 9 dS m−1). Salinity negatively affected plant growth assessed by leaves number, leaves length, shoot dry weight, corms number and corms weight. Moreover, there was a clear direct correlation between higher salinity value and less plant growth. Different effects due to salinity and nitrogen were evident in terms of the number and length of leaves during the growing season from day 60 after first irrigation (DAF) and achieved a peak after 90 DAF. Salt stress also affected the ions balance, as Na+, Cl− and Ca2+ were enhanced and K+ was reduced, thereby damaging the plants. Nitrogen partially mitigated the negative impacts of salinity on plant growth and ions balance, although this compensatory effect was observed when nitrogen supply was set at 50 kg N ha−1. For example, in 2019–2020, the losses in shoot dry weight due to 9 dS m−1 salinity amounted to 47%, 44% and 54%, at 0, 50 and 100 kg N ha−1 respectively, thus indicating a less negative effect of salinity at 50 kg N ha−1. Moreover, at 100 kg N ha−1 the negative effect of salinity was stronger for six and nine dS m−1. Our findings suggested that the optimum N supply (50 kg N ha−1) strengthened the plant under non-saline and moderately saline (6 dS m−1) conditions, and consequently improved salt tolerance. [ABSTRACT FROM AUTHOR]

Rare earth elements (REEs) are essential components of modern technologies and are often challenging to acquire from natural resources. The demand for REEs is so high that there is a clear need to develop efficient and environmentally-friendly recycling methods. In the present study, freeze-dried cells of the extremophile Galdieria sulphuraria were employed to recover yttrium, cerium, europium, and terbium from quaternary-metal aqueous solutions. The biosorption capacity of G. sulphuraria freeze-dried algal biomass was tested at different pHs, contact times, and biosorbent dosages. All rare earths were biosorbed in a more efficient way by the lowest dose of biosorbent, at pH 4.5, within 30 min; the highest removal rate of cerium was recorded at acidic pH (2.5) and after a longer contact time, i.e., 360 min. This study confirms the potential of freeze-dried cells of G. sulphuraria as innovative ecological biosorbents in technological applications for sustainable recycling of metals from e-waste and wastewater. [ABSTRACT FROM AUTHOR]

Rare earth elements (REEs) are essential components of modern technologies and are often challenging to acquire from natural resources. The demand for REEs is so high that there is a clear need to develop efficient and environmentally-friendly recycling methods. In the present study, freeze-dried cells of the extremophile Galdieria sulphuraria were employed to recover yttrium, cerium, europium, and terbium from quaternary-metal aqueous solutions. The biosorption capacity of G. sulphuraria freeze-dried algal biomass was tested at different pHs, contact times, and biosorbent dosages. All rare earths were biosorbed in a more efficient way by the lowest dose of biosorbent, at pH 4.5, within 30 min; the highest removal rate of cerium was recorded at acidic pH (2.5) and after a longer contact time, i.e., 360 min. This study confirms the potential of freeze-dried cells of G. sulphuraria as innovative ecological biosorbents in technological applications for sustainable recycling of metals from e-waste and wastewater. [ABSTRACT FROM AUTHOR]

Purpose: Pollution from oil operations; exploration, drilling, transfer, transport, refinery and distribution reduce soil quality, and results in the removal of a large amount of soil from annual utilization cycles. Soil quality is an essential asset of sustainable development and is negatively affected by erosion and anthropogenic activity. Co-composting is a biological technique used in the bioremediation of soils, which was investigated in this study. Materials and methods: This study focused on the remediation of 1200 m3 of saline contaminated soil from an oil-polluted operational area in Iran. The initial total petroleum hydrocarbon (TPH) content of the soil was between 6.9 and 17.1 g kg−1 and was contaminated with heavy oil. Initial water repellency of the soil was between 1500 and 12,500 S. The remediation procedure commenced with trials in which organic waste of a local sugarcane sugar factory, mixed urea, sugar, and compost mixtures was added to contaminated soils. Results: After irrigation and aeration of piles of organic materials and soil over 3 months of operation, the TPH reduced from 4.86, 6.52, and 9.89 to 0.068, 0.080, and 0.109 g kg−1, in the moderately, highly, and very highly polluted soil piles respectively. At the end of the remediation project, following gas chromatography analysis of contaminant content, and in accordance with governmental authorities, recovered soils were added to the surrounding environment to the support growth of the natural ecosystem. Conclusion: Soil recovery and remediation utilizing valorization and complimentary local industries have a transferable quality that may be adapted to additional vulnerable sites in droughted and variable edaphic and climatic conditions. [ABSTRACT FROM AUTHOR]

Two field experiments were conducted to evaluate six Salicornia species (Salicornia bigelovii Torr., S. europaea L., S. persica Gorgan ecotype, S. persica Urmia ecotype, S. sinus persica Bushehr ecotype, and S. persica Central Plateau ecotype) at different planting dates and densities under irrigation with Persian Gulf water. Evaluated planting dates were 14 November and 18 December 2016 and 16 January, 8 February, 8 March, and 28 March 2017. Examined planting densities included 13, 20, and 40 plant m−2. Only S. bigelovii and S. europaea produced measurable yield in all planting dates. The highest dry weight (651.1 gm−2) was obtained in S. sinus persica (Bu) planted on 8 February. Dry weight of S. bigelovii, S. europaea, S. sinus persica Bushehr, S. persica Central Plateau, S. persica Gorgan, and S. persica Urmia planted on 8 March were 174.2, 220.7, 542.5, 240.9, 158.0, and 147.5 g m−2, respectively. The ash contents of S. bigelovii, S. europaea, S. sinus persica Bushehr, S. persica Central Plateau, S. persica Gorgan, and S. persica Urmia were 46.3%, 45.0%, 49.6%, 49.6%, 50.0%, and 53.1%, respectively. Sodium and chloride contents of different Salicornia species varied from 13–15% and 16–17%, respectively. The oilseed content of S. bigelovii and S. sinus persica Bushehr was about 24.0% for both species. The highest and lowest dry weight, from the second experiment, were for S. sinus persica Bushehr and S. persica Central Plateau, respectively, in all planting density. The highest dry weight equal to 1336.2 gm−2 was obtained for S. sinus persica Bushehr in 40 plant m−2 density. Under such conditions, forage production potential of Salicornia is more achievable rather than seed production. Nevertheless, high ash content is a serious constraint to direct consumption by livestock; therefore, determining the nutritional value of Salicornia fodder requires further evaluations. [ABSTRACT FROM AUTHOR]

Forecasting nitrate concentration in rivers is essential for environmental protection and careful treatment of drinking water. This study shows that nonlinear autoregressive with exogenous inputs neural networks can provide accurate models to predict nitrate plus nitrite concentrations in waterways. The Susquehanna River and the Raccoon River, USA, were chosen as case studies. Water discharge, water temperature, dissolved oxygen, and specific conductance were considered exogenous inputs. The forecasting sensitivity to changes in the exogenous input parameters and time series length was also assessed. For Kreutz Creek at Strickler station (Pennsylvania), the prediction accuracy increased with the number of exogenous input variables, with the best performance achieved considering all the variables (R2 = 0.77). The predictions were accurate also for the Raccoon River (Iowa), although only the water discharge was considered exogenous input (South Raccoon River at Redfield—R2 = 0.94). Both short- and long-term predictions were satisfactory. [ABSTRACT FROM AUTHOR]

The lanthanides are among the rare earth elements (REEs), which are indispensable constituents of modern technologies and are often challenging to acquire from natural resources. The demand for REEs is so high that there is a clear need to develop efficient and environmentally-friendly recycling methods. In the present study, living cells of the extremophile Galdieria sulphuraria were used to remove four REEs, Yttrium, Cerium, Europium, and Terbium, from single- and quaternary-metal aqueous solutions. Two different strains, SAG 107.79 and ACUF 427, were exposed to solutions buffered at pH 2.5, 3.5, 4.5, and 5.5. Our data demonstrated that the removal performances were strain and pH dependent for all metal ions. At lower pH, ACUF 427 outperformed SAG 107.79 considerably. By increasing the pH of the solutions, there was a significant surge in the aqueous removal performance of both strains. The same trend was highlighted using quaternary-metal solutions, even if the quantities of metal removed were significantly lower. The present study provided the first insight into the comparative removal capacity of the Galdieria sulphuraria strains. The choice of the appropriate operational conditions such as the pH of the metal solutions is an essential step in developing efficient, rapid, and straightforward biological methods for recycling REEs. [ABSTRACT FROM AUTHOR]

This work provides a comprehensive review of research on the cold-bonding pelletization process used to produce lightweight aggregates (LWAs) using waste materials, to valorize the waste and, at the same time, minimize risks related to disposal. Research investigating various aspects of the cold-bonding process highlight: i) feasible mix-designs for pellet production; ii) the most relevant operating parameters affecting the process; and iii) the potential applications of the LWAs produced. The analysis gives a wide overview of the fundamental key-points that control the cold-bonding process. Data comparison provides a useful way to identify the optimal process conditions to allow development of optimum products. This involves the selection of the correct mix-design, including suitable binders and potential additives, and the selection of appropriate operating conditions, which are a function of the waste investigated, and/or waste mix characteristics. The review proposes an optimized approach to experimental studies on cold-bonding processes that has potential to enhance future process performance. Moreover, the present work provides a complete framework useful for decision-making for both manufacturers and researchers working to use this promising technique. [ABSTRACT FROM AUTHOR]

This study proposes a comparison of different ex situ technologies aimed at the removal of polycyclic aromatic hydrocarbons from marine sediments in terms of performances, costs and energy balance. In accordance with the principles of water-energy nexus, anaerobic bioremediation, soil washing and thermal desorption were investigated under low liquid phase and temperature conditions using phenanthrene (PHE) as model compound. After 42 days of anaerobic bioremediation, the highest PHE biodegradation of 68 and 64% was observed under denitrifying and methanogenic conditions, respectively, accompanied by N2 and CH4 production and volatile fatty acid accumulation. During soil washing, more than 97% of PHE was removed after 60 min using a solid-to-liquid ratio of 1:3. Along the same treatment time, low-temperature thermal desorption (LTTD) allowed a PHE removal of 88% at 200 °C. The economic analysis indicated that LTTD resulted in a higher cost (i.e. 1782 € m−3) than bioremediation and soil washing (228 and 371 € m−3, respectively). The energy balance also suggested that bioremediation and soil washing are more sustainable technologies as a lower required energy (i.e. 16 and 14 kWh m−3, respectively) than LTTD (i.e. 417 kWh m−3) is needed. [ABSTRACT FROM AUTHOR]

Agricultural wastes derived from olive oil production were used in wastewater engineering as lead, cadmium, and nickel ions sorbents. Experiments were carried out in distilled water (Troom) by the use of packed bed columns filled with grains (1–3 mm) which were eluted with single and multimetal solutions in the 3–10 mg/L concentration range. Operations were performed with different sorbent dosage (4–8 g) at flow rates ranging 0.3–0.7 L/h until exhaustion. Best retention capacities were 8.15, 3.5, and 2.9 mg/gsorbent respectively for Pb+2, Cd+2, and Ni+2 in the case of the multimetal system (0.3 L/h, 8 g of sorbent, and 10 mg/L influent solution). EDX analysis carried out on the sorbent surface showed that the wt % ratios between the sorbed metals were similar to the ratios between the column overall capacities. Inter-diffusion of the ions in the Nernst stationary liquid film around the particle was identified as the step which controls the kinetics of the process. Exhausted wastes were successively recycled in cement mortars together with another aggregate as exhausted porous glass in order to obtain a lightweight composite with good consistency and interesting mechanical resistances. [ABSTRACT FROM AUTHOR]

A kinetic study on the photo-catalytic degradation of bio-persistent micro-pollutants, as methyl red and methylene blue dyes, was carried out on an innovative unit by changing the hydraulic and hydrodynamic parameters of the system. The catalyst (TiO2, anatase) was embedded into a cement matrix and deposited at the bottom of a channel to activate the UVB photo-degradation reactions. The influence of the catalyst dosage, substrate concentration c0, and pH was evaluated on the degradation rates. The optimum catalytic dose was obtained at 0.79 g/cm3 while the best results were observed at 0.7 mg/L influent dye concentration. The pH of the solution influenced the sorption phenomena because the charge of the substrates functional groups as well as the charge of the catalyst surface were affected by this parameter. Different unit geometries, hydraulic loads (hw) and gradients (i) affected speed and flow-rate (Q) of the liquid phase and, as a consequence, the irradiated retention times (Irt) of the substrates to the UV/TiO2 system. Kinetics resulted faster at increasing flow-rates of the liquid flowing through the channel, constant the hydraulic load, whereas the increase in the hydraulic load did not improve the performances. Finally, degradation rates slightly decreased after the increase in the hydraulic gradient of the channel. [ABSTRACT FROM AUTHOR]

Biomethane is the most energy-efficient biofuel and it is also environmentally advantageous because it can be utilized as a partial alternative to fossil fuels for heat and electricity generation when an adequate biogas upgradation strategy is followed. Several recent studies have been conducted to identify the renewable sources of biohydrogen, such as biohydrogen production from unused glycerol from biodiesel production, oil palm waste hydrolysate, second-generation biomass, forestry biomass and kitchen waste. [Extracted from the article]

33744268 16 Ahmed W., Mehmood S., Núñez-Delgado A., Ali S., Qaswar M., Khan Z.H., Ying H., Chen D.Y. Utilization of Citrullus lanatus L. seeds to synthesize a novel MnFe2O4-biochar adsorbent for the removal of U(VI) from wastewater: Insights and comparison between modified and raw biochar. With the Topic "New Research on Detection and Removal of Emerging Pollutants" (https://www.mdpi.com/topics/Emerging%5fPollutants) closed to new submissions, the Editors would like to share some comments on it. 10.3390/pr11010006 14 Wang S., Zhang W., Jia F., Fu H., Liu T., Zhang X., Liu B., Núñez-Delgado A., Han N. Novel Ag3PO4/boron-carbon-nitrogen photocatalyst for highly efficient degradation of organic pollutants under visible-light irradiation. [Extracted from the article]

The present work aims to provide a comprehensive review of the experimental studies focusing on municipal solid waste incineration fly-ash (FA) treatments that are required before the application of advanced processes aimed at their final reuse or safe disposal. The investigated pre-treatments are divided into three categories: (1) water washing/chemical leaching; (2) electrodialysis; and (3) thermal separation. Analysed aspects include: (1) process efficiency; (2) effect on FA physical–chemical characteristics; and (3) process applicability as a function of secondary FA treatment steps which are generally required for final disposal or reuse of the remediated waste. Investigations related to these elements allows a determination of the efficacy and the operational convenience of a specific pre-treatment to achieve a proper FA remediation level. A comparison of studies in the literature provides a thorough source and a useful basis for correctly addressing future experimental activities and research efforts. The discussion of the results provides the basis for the development of a suitable methodology to optimize the environmentally sustainable reuse or safer disposal of treated FA. [ABSTRACT FROM AUTHOR]

This paper deals with the possibility of using perlite as a lead ion sorbent from industrial wastewater. Dynamic (laboratory column) operations were carried-out using beads, which were percolated by metals in a 2–10 mg·L−1 concentration range. To this purpose, lead ion solutions were eluted in columns loaded with different amounts of sorbent (2–4 g) within a 1–2 mm bead size range, at 0.15–0.4 L·h−1 flow-rates. Tests were performed to complete sorbent exhaustion (column breakthrough). The highest retention was obtained at 0.3 L·h−1, with 4 g of perlite and 10 mg·L−1 of influent, lead ion concentration. Film diffusion control was the kinetic step of the process in the Nerst stationary film at the solid/liquid interface. At the end of the sorption, perlite beads were used as lightweight aggregates in the construction field (i.e., for the preparation of cement mortars). Specifically, conglomerates showing different weights and consequently different thermal insulating and mechanical properties were obtained, with potential applications in plaster or panels. [ABSTRACT FROM AUTHOR]

This paper presents the results of an experimental study aimed at investigating the applicability of ethylenediamine-N,N0-disuccinic acid (EDDS) as a washing solution for the remediation of Pb-contaminated soil. All aspects of the treatment are analyzed and optimized, including the reuse and the final disposal of the EDDS spent solution. Different molar concentrations of the washing solutions and the efficiencies of varying solid/liquid ratio are tested at different pH values. More than 90% of the mobile Pb fraction is removed in about 24 h at pH 6. Accordingly, soil toxicity strongly decreases as a consequence of the treatment. The regenerated solution exhibits a reduced, but not negligible, extractive capacity. The total extraction of Pb is approximately 50% of the initial value after one regeneration cycle, and almost 20% after a second regeneration cycle. Respirometric tests, conducted using an activated sludge sampled in a municipal wastewater treatment plant, indicate that the spent solutions are not biodegradable, but they do not exert any toxic effect on the biomass. On the contrary, tests on regenerated solutions displayed the same biodegradability as the fresh ones. [ABSTRACT FROM AUTHOR]

Contaminated soil has become a growing issue in recent years. The most common technique used to remove contaminants (such as metals) from the soil is the soil washing process. However, this process produces a final effluent containing chelating agents (i.e., ethylenediaminedisuccinic acid, also known as EDDS) and extracted metals (i.e., Cu, Fe, and Zn) at concentrations higher than discharge limits allowed by the Italian and Brazilian environmental law. Therefore, it is necessary to develop further treatments before its proper disposal or reuse. In the present study, soil washing tests were carried out through two sequential paths. Moreover, different artificial sunlight-driven photocatalytic treatments were used to remove Cu, Zn, Fe, and EDDS from soil washing effluents. Metal concentrations after the additional treatment were within the Brazilian and Italian regulatory limits for discharging in public sewers. The combined TiO-photocatalytic processes applied were enough to decontaminate the effluents, allowing their reuse in soil washing treatment. Ecotoxicological assessment using different living organisms was carried out to assess the impact of the proposed two-step photocatalytic process on the effluent ecotoxicity. [ABSTRACT FROM AUTHOR]

The study analyzes the presence and the origin of heavy metals in environmental compartments affected by anthropogenic activities. The paper presents the results of a field study performed on the sediments of two of the main small urban creeks of the city of Prague (Czech Republic). The aim of the survey was to verify the presence and bioavailability of heavy metals (Cu, Cr, Ni, Pb, Zn) in the aquatic environment (water as well as bottom sediments), and to assess the source of these pollutants. The results were processed to evaluate the enrichment factor and the partition coefficient, and were statistically analyzed through the analysis of variance and the principal component analysis. Comparison with relevant environmental quality standards showed that measured heavy metal concentrations were always lower than the probable effect concentration (PEC). On the contrary, the threshold effect concentration (TEC) was frequently exceeded. Sequential extraction analysis showed that the bioavailability of studied metals is quite high, suggesting that they could be easily released from the sediment to the aquatic environment. Overall, several sources of pollution, different for the different metals, were identified, all related with anthropogenic factors. [ABSTRACT FROM AUTHOR]

Ultrasonic cleaning is a developed and widespread technology used in the cleaning industry. The key to its success over other cleaning methods lies in its capacity to penetrate seemingly inaccessible, hard-to-reach corners, cleaning them successfully. However, its major drawback is the need to immerse the product into a tank, making it impossible to work with large or anchored elements. With the aim of revealing the scope of the technology, this paper will attempt to describe a more innovative approach to cleaning large area surfaces (walls, floors, façades, etc.) which involves applying ultrasonic cavitation onto a thin film of water, which is then deposited onto a dirty surface. Ultrasonic cleaning is an example of the proliferation of green technology, requiring 15 times less water and 115 times less power than conventional high-pressurized waterjet cleaning mechanisms. This paper will account for the physical phenomena that govern this new cleaning mechanism and the competition it poses towards more conventional pressurized waterjet technology. Being easy to use as a measure of success, specular surface cleaning has been selected to measure the degree of cleanliness (reflectance) as a function of the process's parameters. A design of experiments has been developed in line with the main process parameters: amplitude, gap, and sweeping speed. Regression models have also been used to interpret the results for different degrees of soiling. The work concludes with the finding that the proposed new cleaning technology and process can reach up to 98% total cleanliness, without the use of any chemical product and with very low water and power consumption. [ABSTRACT FROM AUTHOR]

The photo-catalytic degradation of a textile azo-dye as Methyl Orange was studied in an innovative unit constituted by a channel over which a layer of titanium dioxide (TiO2) catalyst in anatase form was deposited and activated by UVB irradiation. The degradation kinetics were followed after variation of the chemical, physical, and hydraulic/hydrodynamic parameters of the system. For this purpose, the influence of the TiO2 dosage (g/cm3), dye concentration (mg/L), pH of the solution, flow-rate (L/s), hydraulic load (cm), and irradiation power (W) were evaluated on the degradation rates. It was observed that the maximum dosage of TiO2 was 0.79 g/cm3 while for higher dosage a reduction of homogeneity of the cement conglomerate occurred. The Langmuir–Hinshelwood (LH) kinetic model was followed up to a dye concentration around 1 mg/L. It was observed that with the increase of the flow rate, an increase of the degradation kinetics was obtained, while the further increase of the flow-rate associated with the modification of the hydraulic load determined a decrease of the kinetic rates. The results also evidenced an increase of the kinetic rates with the increase of the UVB intensity. A final comparison with other dyes such as Methyl Red and Methylene Blue was carried out in consideration of the pH of the solution, which sensibly affected the removal efficiencies. [ABSTRACT FROM AUTHOR]

Digestate, as an urban solid waste, was considered as an innovative adsorbent for colorant polluted wastewater. Batch adsorption experiments were carried out using digestate as an adsorbent material to remove various dyes belonging to different categories. The removal rate and adsorption capacity of dyes were evaluated and the dose of digestate, contact time, and initial dye concentration were studied. The maximum removal rate was approximately 96% for Methylene Blue. The equilibrium time for the Methylene Blue was 4 h, while for other dyes, a longer contact time was required to reach the equilibrium. The suspicion of colloidal matter release into the solution from solid fraction of the digestate led to the investigation of the consequence of a washing step of the digestate adsorbent upstream the adsorption experiment. Washed and not washed adsorbents were tested and the differences between them in terms of dye removal were compared. Moreover, experimental data were fitted by pseudo-first order, pseudo-second order, and intra-partial diffusion kinetic models as well as Langmuir, Freundlich, and Sips isotherm models. The results from fitted models showed that the adsorption of various dyes onto the digestate was mostly well fitted by the Langmuir isotherm and pseudo-second-order kinetic model. [ABSTRACT FROM AUTHOR]

The recycling and reuse of solid wastes can be considered important challenges for civil and environmental applications in the frame of a more sustainable model of development and the consumption of new resources and energy [[1]]. This silane-treated cellulose aerogel exhibited high absorption capacities of 1091 ± 19.6%, 1237 ± 17.6% and 1247 ± 21.1% by weight gain for waste motor oil, diesel and gasoline, respectively. For this purpose, simulated Ce-bearing radioactive soil waste was immobilized by the self-propagating high-temperature synthesis (SHS) of forms containing 5-25% of contaminated material and which were characterized by the analysis of phase composition, microstructure and chemical durability. [Extracted from the article]

A porous waste glass (RWPG = recycled waste porous glass) was used in wastewater treatments for the removal of lead ions from single, binary, and ternary metal solutions (with cadmium and nickel ions). Experiments were performed in columns (30 cm3, 10 g) filled with 0.5–1 mm beads till complete glass exhaustion (breakthrough). In the case of single and binary solutions, the columns were percolated at 0.2 Lh−1 (2 mg Me+2 L−1); in the case of ternary solutions, the columns were percolated at 0.15–0.4 Lh−1 (2 mg Me2+ L−1) and with 2–5 mg Me2+ L−1 influent concentration (0.2 Lh−1). Lead ions were removed mainly by ion exchange and also by adsorption. From a kinetic point of view, the rate controlling step of the process was the interdiffusion of the lead ions in the Nernst stationary liquid film around the sorbent. The uptake of the metals and the glass selectivity were confirmed by Energy Dispersive X-ray spectroscopy (EDX) analysis. After lead retention process, glass beads were reused as lightweight aggregates for thermal insulating and environmental safe mortars. [ABSTRACT FROM AUTHOR]